Diagnostics of Fuel and Exhaust System Faults

Excessive fuel consumption
1 Air cleaner filter element contaminated or airflow restricted (refer to Maintenance and Adjustment).
2 Ignition timing incorrect (refer to Engine Electrical System).
3 Emission control systems not functioning correctly (refer to Engine Management).
4 Fuel injection system faulty (refer to Fuel and Exhaust Systems).
5 Tire pressure low, or wheels of incorrect size fitted (refer to Maintenance and Adjustment).
6 Brakes dragging (refer to Maintenance and Adjustment and Brakes).

Fuel leakage or strong smell of petrol
1 Fuel tank, fuel lines or their connections damaged mechanically or by corrosion (refer to Fuel and Exhaust Systems).
2 Fuel tank overfilled.
3 Evaporative emission canister filter blocked (refer to Maintenance and Adjustment and Engine Management).
4 Internal components of fuel injectors damaged or excessively worn (refer to Fuel and Exhaust Systems).

Exhaust system excessively noisy or smoking
1 Exhaust gas leaks at exhaust manifold or exhaust system joints (refer to Maintenance and Adjustment and Fuel and Exhaust Systems).
2 Exhaust silencers or pipes damaged mechanically or by corrosion (refer to Maintenance and Adjustment and Fuel and Exhaust Systems).
3 Exhaust system contacting body or suspension components while driving due to damaged mounting rubbers (refer to Maintenance and Adjustment and Fuel and Exhaust Systems).